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Outbreak Notification Infection Control Coordinator at a central Texas hospital called the regional office of the state health department ~30 people had presented to the hospital’s emergency room during the previous 24 hours with gastrointestinal symptoms All of the ill persons had eaten a picnic supper the previous evening at a local ranch

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Case Definition Any three of the following symptoms: Diarrhea, fever, nausea, cramps, vomiting Diarrhea defined as > 3 loose stools in a 24 hour period OR culture positive stool specimen AND ate the picnic supper

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Conclusions 109 persons developed salmonellosis following consumption of a bean dish and/or chicken served at a ranch picnic Either raw chicken or an ill foodhandler could have been the source of the bacteria The beans were cross-contaminated with the bacteria in the kitchen

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Summary: Old Paradigm Outbreak notification results from detection of more than the expected number of cases for the place and time Pathogen often unknown until after outbreak detection Epidemiologic investigation aims at identifying the exposure Laboratory results identify the agent and may confirm the epidemiologic findings implicating a source of exposure (food item)

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Outbreak Notification 2 cases of Salmonella Typhi identified in Houston area Cases had same strain of S. Typhi by PFGE 4 additional cases of the same strain reported over the next several weeks 1 Houston area 2 Austin area 1 San Antonio None of the 6 cases had recent international travel

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Oyster Traceback and Plant Investigation Oysters traced for all 6 cases to the same lease in Galveston Bay Samples of frozen product from same harvest area and timeframe, and specimens from oyster plant workers tested negative for S. Typhi

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Conclusions 6 cases of typhoid fever were linked to raw oyster consumption Implicated oysters were harvested from the same area of Galveston Bay by the same harvester The source of the oyster contamination was not identified Could have happened during harvesting Could have happened at the lease site

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Summary: New Paradigm Outbreak notification results from detection of an increased number of cases of a particular agent or strain of an agent by a laboratory –Pathogen identified at time of outbreak detection Epidemiologic investigation aims at identifying the exposure

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Recent Outbreaks with Texas Cases Illustrating the New Paradigm Peanut butter-associated Salmonella Tennessee –Outbreak detection based on large number of cases reported to CDC’s PulseNet with unusual serotype of Salmonella and one of 3 similar strains –Multistate epidemiologic investigation, using common questionnaire, identified 2 brands of peanut butter as suspect vehicles 2 brands produced in same plant